/Engine/Source/Developer/FunctionalTesting/Classes/FunctionalTest.h
Writes the current set of performance stats records to a csv file in the profiling directory. An additional directory and an extension override can also be used.
void WriteLogFile ( const [FString](API\Runtime\Core\Containers\FString) & CaptureDir, const [FString](API\Runtime\Core\Containers\FString) & CaptureExtension )